Robotic grippers

Abstract

A robotic gripper may be configured to dexterously manipulate an article. The robotic gripper may include two or more fingers containing one or more rotatable contacts each. The rotatable contact may transition between a rotation mode and a braking mode such that the contacts are free to rotate in the rotation mode and are prevented from being rotated in the braking mode. In some instances, the robotic gripper may make contact with the article via the contact pads. Thus, the robotic gripper may dexterously manipulate the article via the contact pads and brake.

The invention claimed is: 
     
       1. A robotic gripper comprising:
 a first gripper finger and a second gripper finger, each of the first and second gripper fingers comprising:
 a body portion; 
 a rotatable contact pad configured to contact an article and operatively connected to the body portion; and 
 a brake configured to selectively maintain a fixed orientation of the rotatable contact pad relative to the body portion when engaged, 
 
 wherein the rotatable contact pad of the first gripper finger and the rotatable contact pad of the second gripper finger are adapted to rotate relative to the first and second gripper fingers about a single common axis of rotation, and wherein the first and second gripper fingers and the brake are configured such that a braking force applied by the brake is independent of a gripping force applied to the article by the first and second gripper fingers. 
 
     
     
       2. The robotic gripper of  claim 1 , wherein the first and second gripper fingers are configured to be displaced towards one another to grip an article between the rotatable contact pads of the first and second gripper fingers. 
     
     
       3. The robotic gripper of  claim 1 , wherein the brake includes at least one selected from a pneumatically actuated diaphragm, a shaft brake, and a disk brake. 
     
     
       4. The robotic gripper of  claim 1 , wherein the brake includes at least one dielectric configured to prevent the rotation of a shaft through electroadhesion. 
     
     
       5. The robotic gripper of  claim 1 , wherein the robotic gripper further includes a processor configured to operate the robotic gripper. 
     
     
       6. The robotic gripper of  claim 5 , wherein the processor is configured to control the robotic gripper to perform the steps of:
 gripping an article in a first orientation; 
 translating the article; 
 pivoting the article between the first orientation and a second orientation; and 
 placing the article in the second orientation. 
 
     
     
       7. The robotic gripper of  claim 6 , wherein the processor is configured to perform the step of pivoting the article between the first orientation and a second orientation by disengaging the brake. 
     
     
       8. The robotic gripper of  claim 7 , wherein the processor is configured to perform the step of pivoting the article between the first orientation and a second orientation under a gravitational field. 
     
     
       9. The robotic gripper of  claim 7 , wherein the processor is configured to perform the step of reengaging the brake before placing the article in the second orientation. 
     
     
       10. A method of operating a robotic gripper comprising:
 gripping an article between a first rotatable contact pad and a second rotatable contact pad in a first orientation, wherein the first and second rotatable contact pads are positioned on different gripper fingers of a robotic gripper; 
 engaging a brake before gripping the article between the first and second rotatable contact pads; 
 rotating the first and second rotatable contact pads relative to the different gripper fingers about a single common axis of rotation to pivot the article into a second orientation; and 
 preventing rotation of the first and second rotatable contact pads to maintain the article in the second orientation. 
 
     
     
       11. The method of  claim 10 , wherein gripping the article between the first and second rotatable contact pads of the robotic gripper includes displacing the first and second rotatable contact pads towards one another. 
     
     
       12. The method of  claim 10 , wherein rotating the first and second rotatable contact pads includes disengaging the brake. 
     
     
       13. The method of  claim 12 , wherein engaging the brake includes providing a pneumatic pressure to at least one diaphragm and disengaging the brake includes removing the pneumatic pressure from the at least one diaphragm. 
     
     
       14. The method of  claim 12 , wherein engaging the brake includes providing an electric potential to a dielectric material associated with the brake and disengaging the brake includes removing the electric potential from the dielectric material. 
     
     
       15. The method of  claim 10 , wherein engaging the brake includes applying a braking force independent of a gripping force applied to the article. 
     
     
       16. A method of operating a robotic gripper comprising:
 gripping an article between a first rotatable contact pad and a second rotatable contact pad of a robotic gripper in a first orientation, wherein gripping the article includes applying a gripping force to the article via the first and second rotatable contact pads, wherein the first and second rotatable contact pads are positioned on different gripper fingers of the robotic gripper and are adapted to rotate relative to the different gripper fingers about a single common axis of rotation; and 
 selectively applying a braking force to the first and second rotatable contact pads to selectively maintain the orientation of the first and second rotatable contact pads relative to the robotic gripper, wherein the braking force is independent of the gripping force. 
 
     
     
       17. The method of  claim 16 , wherein selectively applying the braking force includes providing or removing the braking force to rotate the first and second rotatable contact pads to pivot the article into a second orientation. 
     
     
       18. The method of  claim 17 , further comprising preventing rotation of the first and second rotatable contact pads to maintain the article in the second orientation.